Measuring the Mechanical Parameters of Fragmented Earth and Asteroid Rocks with Micro-rme
Xuhai TANG1#+, Yiheng ZHANG1, Jingjing XU1, Adriana PALUSZNY2, Quansheng LIU1
1Wuhan University, China, 2Faculty of Engineering, Department of Earth Science & Engineering, Imperial College London, United Kingdom

Measuring the mechanical property of rocks accurately is critical, however, in many situations, it is challenge to obtain intact and standard rock specimens required by macroscale rock mechanics experiments (macro-RME), such as MTS tests. For example, the rocks are frequently fragmented and muddy inside faults, which leads to the difficulty of drilling and sampling. The phenomenon of core disking also widely exist due to high-stress. Additionally, the future extraterrestrial human activities, such as resources exploitation and base construction on Mars, need the aid of geotechnical engineering technology. Currently, there are only two approaches for humans to obtain the rock samples beyond Earth: sample-return activities by spacecraft and meteorite investigation. Meteorites are rare, expensive, small in size and arbitrary in shape, so it is difficult to process them into standard rock samples required by traditional macro-RME. In this paper, a technique is developed to measure the mechanical property of small and any-shaped rocks based on microscopic Rock Mechanics Experiments (micro-RME), in order to investigate granites and NWA13618 meteorites. First, using nanoindentation tests, the elastic modulus of rock-forming minerals is measured. Then, with the results of micro-RME, the upscaling modelling method is developed to get the macroscale mechanical property of these rocks.